The invention discloses a novel sensor
access bus protocol. In the process of normal inspection, a fire alarm application is sent to an alarm controller by encoding
terminal equipment with a fire alarm through a
bus; after the application is received by the alarm controller, a fire alarm inspection command is immediately sent to the encoding
terminal equipment, and the process of normal inspection is interrupted at the same time; after the fire alarm inspection command is received, an address of the encoding
terminal equipment is sent back by the encoding terminal equipment in a fire
alarm state through the
bus; a normal inspection command is sent to the encoding terminal equipment by the alarm controller in accordance with the received address, so as to confirm whether the encoding terminal equipment is really in the fire
alarm state or not; if the encoding terminal equipment is really in the fire
alarm state, a fire alarm confirming command is sent to the encoding terminal equipment; and if a response
signal of the encoding terminal equipment is in a fire alarm confirming state, the encoding terminal equipment is finally confirmed to be in the fire alarm state. According to the technical scheme, the traditional passive inspection is overcome, an alarm point can be accurately and reliably positioned, a
false alarm caused by factors such as environment is avoided, and stability and reliability of
bus protocol communication are guaranteed.